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-   -   Battery help? (https://www.nopistons.com/2nd-generation-specific-17/battery-help-76336/)

Iowan82 04-25-2012 02:25 AM

Battery help?
 
So correct me if im wrong but the solid black batter cable is positive? and ya? well when i put that solid black wire on the negative it the motor runs without the key....like it turns like it should but when i put it on the positive everything works..except the engine..it makes a clicking noise and ya help would be appreciated. by the way the motor was put in by the previous owner and he didn't mark anything but we got it all together and now this lol also its an 88 vert N/a

jdonnell 04-26-2012 06:19 PM

Re: Battery help?
 
Black is the ground which is negative (-); red is positive (+). Not sure about your problem there on how to fix it?

Akagis_White_Comet 05-06-2012 05:40 AM

Re: Battery help?
 
According to the S4 wiring diagram, Solid Black is Positive, Black/Yellow is Ground/Negative. This sounds like the previous owner was rushed when hooking up the starter cables and the positive cable is making contact with the ignition switch terminal on the starter (1/4" quick disconnect between the two stud terminals). Result is that as soon as Solid Black meets positive terminal, you get a cranking engine. With polarity reversed, you get a positive grounded electrical system where some items may work but quite a few won't.

Honestly, it sounds like your car is due for fresh cables anyway. Aaron Cake on the other forum has a great how-to on making them using welding cable, though I have a couple additions you should do as well. Here is a link to his article:
http://www.aaroncake.net/RX-7/grounding.htm

The main thing is to de-loom the cables from the Engine Harness. You'll see that the positive cable has two splices in it: alternator and fuse box. More accurately, they're stapled together. Cut these off where they meet the larger cable that runs from the battery to the starter. After you've extracted the alternator and starter cables from the car, they should go right into the trash where they belong.

At your local welding supply store, purchase 11ft of 4awg welding cable and 8 lugs. The stock alternator's output stud and the body's ground point are both M6x1.0, while all other connections are M8 or M10. You'll also need a suitable lug for the fuse panel's existing cable too. This arrangement has three lugs on the positive terminal, so I'd suggest getting some marine battery terminals as well.

The following lengths are reasonably close to the originals, while giving you some slack to route and loom everything neatly:

4ft for battery positive to starter
2ft for battery negative to main body ground
2ft for main body ground to starter body
3ft for alternator to battery positive

If using a butane torch to solder the lugs, make sure it is HOT and the solder flows into the cup easily. You'll be suprized at how much solder it takes and how long it takes to heat it up enough. Once it is hot enough, the cable should push relatively easily into the molten solder. If the cable doesn't go in easily, heat the lug more. Having a torch that will stay put really helps with this. After it is cooled off, pull on the cable firmly a couple times. A properly soldered cable will be rock solid.

Here in Ohio, DeLille Oxygen sells the cable for $1.50/ft and lugs for $0.75 each. Add some red heat shrink on all the positive cables and you should be all set. I personally take it a step further and label everything with a labelmaker so there is no mistaking it ever again.

Iowan82 05-08-2012 01:25 AM

Re: Battery help?
 
Hey thanks i was confused about this damn thing cuz i thought that what you had said was right then the other person had said something different then it was weird and now this so imma try it tomorrow and see how it goes as far as the new plugs im not skilled enough or smart enough to do it i also dont have the cash or supplies im only 17 and i don't ask for funds from my parents i want it to be all me haha


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